"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Saturday, January 21, 2017

Enhanced Risk of Severe Potential Remains Real Late Sunday

Uprooted Tree Remains Post-Matthew from October - Cape Canaveral
TODAY: Warmer and a bit muggier today as advertised with developing S-SW wind this afternoon. High in the lower 80Fs mostly though some areas might see a mid-80F. Any rain/storms would remain north of I-4. 

Meanwhile. the first severe weather threat period moves in across the Panhandle region mainly from Tallahassee and west. A few tornado warnings are already on the horn further west .

Radar simulations from the HRRR model  indicate the chance for a high end tornado near Pensacola toward Panama City area of possible EF3 strength. (that  is only a forecast, but the 'threat' is real), but that is from only one run (which is done hourly) from one short term model. On the other hand, other guidance is not nearly as menacing. Regardless, an enhanced severe threat remains with the activity projected to impact that area late morning hours toward noon time.

SUNDAY: Nice start to the day with increasing SW. The next episode of severe enters the picture first again toward the Panhandle sometime late morning, possibly a bit further east than round one, which then continues to press east and expand southward along what appears would be a bit of a broken, QLCS squall line.

As being noted in varying models, timing remains an issue as to when North Central to Central Direct will be impacted. There appears to be agreement though, that some kind of a squall line type formation will develop early to mid afternoon from near JAX SSW to west of Tampa which will then strengthen and expand southward into near sunset; however, not all focus should be on the line if it were to develop. 

Some guidance also indicates discrete , isolated storm cells forming acorss 'anywhere' Central Florida after 4pm toward dark and moving off the east coast. Though small and quick moving if so, such activity in the given situation can produce a quick tornado and//or strong wind gusts.

As anticipated a low level jet coupled with a 500mb (as opposed to 300mb) jet streak well aloft (500mb is lower in the atmosphere) along with a little bit of directional shear will result in bulk shear (speed shear plus directional shear) which would abet in resultant rapid updraft formation. There will be sufficient instability from day time heating coupled with dewpoints in the upper 60Fs (moisture) to add to the mix. These factors along with low level helicity values in the 200/300 m2/sec2, which is like a cork screwing horizontal wind field racing parallel to the ground will lay down the framework for the Tornado Threat Welcome Mat  ....   as has not been seen in this area for quite a while in regard to potentiality. 

Given the important relevance of this upcoming 'situation' have refrained from making a personal map of where activity might occur and left it up to what is readily available. "IF" I had made a note it 'will mention' that just because areas south of the red hatched (see below) are not in there, the risk for tornado threat remains all the way down the state. Those areas are almost guaranteed any mode of weather will occur during the overnight hours, especially south of Vero Beach.

The Storm Prediction Center has place all of North Central in a 
HATCHED ENHANCED RISK which means a 10% greater risk
 for a significant severe weather event anywhere within 25 NM 
of any given point.

 Enhanced includes EF2 (or higher) tornado strength, straight line winds of 74 mph or greater, or large hail. The greatest threat (in the bloggers opinion only) appears would be wind as noted in previous post up to almost 90MPH , though said wind would be extremely isolated, and/or a tornado. 

Some models (the ones that include this parameter) show 'updraft helicity swats  ' which indicate a rotating updraft (of supercell thunderstorm nature). 
Will not include in the post as those are only a general indication and change , sometimes significantly, in both intensity of the activity as well as location from run to run.

As such, this means that the 4KM - NAM model , for instance, has consistently indicated a few 'particularly nasty storms' based on that parameter alone from near Orlando/Canaveral in general and further north, with the strongest activity north of a line from Brooksville toward Ormond Beach. 

Threat period from far North Central southward toward the Vero Beach area best guess runs from around 3PM (north) to after 10PM (Vero Beach). Some areas as inferred earlier might see activity more than once if activity begins to erupt ahead of the prefrontal broken line, which would be prior to dark. Suspect that the actual organized area, for example, will reach a line from near Titusville toward Sarasota between 8:30pm - 10:00pm but it could be sooner. Other pre-line activity would be prior to or even during sunset time frame.

This does look more now like a 'live coverage' 
situation for local TV Channel networks.

BEYOND: Monday will be breezy with westerly wind, some cloud cover and cooler with the coldest air to arrive Tuesday through Wednesday morning as wind begins to decrease.

WEDNESDAY-THURSDAY: Rapid turn around Wednesday. Very cool in the morning (upper 40Fs inland to lower-mid 50Fs near coast) with a southerly flow develop late morning , sending highs into the upper 70Fs to near 80F in the afternoon as the next front approaches.

FROM FRIDAY ONWARD: The GFS and the CFSV2 are trending on more of a prolonged cool down period, as in, " WINTER PHASE II  "

 Not only cooler, but a few episodes of 'much cooler'. 

For just how long it will go on is questionable and the entire period (into mid-February) would not be cool to cold constantly. Regardless, winter isn't over yet.  The GFS has hinted on a few runs of near freezing to freezing temperatures south of Orlando but mostly indicates mid-upper 30F in the colder areas if such a situation were to develop. This is all well out of range of foreast accuracy anyway, only to say, 'don't be surprised' if local forecasts begin to allude to more chilly weather on tap. 

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